SC Xterra any noticeable difference with a SC working??

I was given a 2003 SC Xterra manual shift with 130,000 miles on it for winter beater. Timing belt, clutch, and waterpump were already done.

Had it in today for a drive belt issue, and was told the SC has not worked for sometime. Apparently a bad knock sensor under the SC had disabled the SC, and once replaced I will have boost again.

My question is, is it worth the repair cost, and would I even notice the differnce?

Mechanic said at 3000ft altitude I would notice a diffence in performance and fuel mileage?

Thoughts?

Thanks
Randy